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Preparation of carbon nanotube bioconjugates for biomedical applications

Abstract

Biomedical applications of carbon nanotubes have attracted much attention in recent years. Here, we summarize our previously developed protocols for functionalization and bioconjugation of single-walled carbon nanotubes (SWNTs) for various biomedical applications including biological imaging; using nanotubes as Raman, photoluminescence and photoacoustic labels; sensing using nanotubes as Raman tags and drug delivery. Sonication of SWNTs in solutions of phospholipid-polyethylene glycol (PL-PEG) is our most commonly used protocol of SWNT functionalization. Compared with other frequently used covalent strategies, our non-covalent functionalization protocol largely retains the intrinsic optical properties of SWNTs, which are useful in various biological imaging and sensing applications. Functionalized SWNTs are conjugated with targeting ligands, including peptides and antibodies for specific cell labeling in vitro or tumor targeting in vivo. Radio labels are introduced for tracking and imaging of SWNTs in real time in vivo. Moreover, SWNTs can be conjugated with small interfering RNA (siRNA) or loaded with chemotherapy drugs for drug delivery. These procedures take various times ranging from 1 to 5 d.

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Figure 1: Overview of the protocol.
Figure 2: A scheme showing conjugation of targeting ligands to SWNTs.
Figure 3: A scheme showing radiolabeling of targeting SWNT bioconjugates.
Figure 4: A scheme showing siRNA conjugation to SWNTs through a disulfide bond.
Figure 5: Functionalization of SWNTs by PL-PEG.
Figure 6: Targeting SWNT bioconjugates for cell labeling and Raman imaging.
Figure 7: Radiolabeled SWNTs for in vivo PET imaging and tumor targeting radiolabeled nanotubes.
Figure 8: CXCR4 expression levels on CEM.NKR cells after various treatments.
Figure 9: Doxorubicin (DOX) on functionalized SWNTs for drug delivery.

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References

  1. Liu, Z., Tabakman, S., Welsher, K. & Dai, H. Carbon nanotubes in biology and medicine: in vitro and in vivo detection, imaging and drug delivery. Nano Res. 2, 85–120 (2009).

    Article  CAS  Google Scholar 

  2. Bianco, A., Kostarelos, K., Partidos, C.D. & Prato, M. Biomedical applications of functionalised carbon nanotubes. Chem. Commun. 571–577 (2005).

  3. Kam, N.W.S., Jessop, T.C., Wender, P.A. & Dai, H.J. Nanotube molecular transporters: internalization of carbon nanotube-protein conjugates into mammalian cells. J. Am. Chem. Soc. 126, 6850–6851 (2004).

    Article  CAS  Google Scholar 

  4. Liu, Z., Winters, M., Holodniy, M. & Dai, H.J. siRNA delivery into human T cells and primary cells with carbon-nanotube transporters. Angew. Chem. Int. Ed. Engl. 46, 2023–2027 (2007).

    Article  CAS  Google Scholar 

  5. Kam, N.W.S., Liu, Z.A. & Dai, H.J. Carbon nanotubes as intracellular transporters for proteins and DNA: an investigation of the uptake mechanism and pathway. Angew. Chem. Int. Ed. Engl. 45, 577–581 (2006).

    Article  CAS  Google Scholar 

  6. Kam, N.W.S., Liu, Z. & Dai, H. Functionalization of carbon nanotubes via cleavable disulfide bonds for efficient intracellular delivery of siRNA and potent gene silencing. J. Am. Chem. Soc. 127, 12492–12493 (2005).

    Article  CAS  Google Scholar 

  7. Kam, N.W.S. & Dai, H. Carbon nanotubes as intracellular protein transporters: generality and biological functionality. J. Am. Chem. Soc. 127, 6021–6026 (2005).

    Article  CAS  Google Scholar 

  8. Sayes, C.M. et al. Functionalization density dependence of single-walled carbon nanotubes cytotoxicity in vitro . Toxicol. Lett. 161, 135–142 (2006).

    Article  CAS  Google Scholar 

  9. Liu, Z. et al. Circulation and long-term fate of functionalized, biocompatible single-walled carbon nanotubes in mice probed by Raman spectroscopy. Proc. Natl. Acad. Sci. USA 105, 1410–1415 (2008).

    Article  CAS  Google Scholar 

  10. Schipper, M.L. et al. A pilot toxicology study of single-walled carbon nanotubes in a small sample of mice. Nat. Nanotech. 3, 216–221 (2008).

    Article  CAS  Google Scholar 

  11. Liu, Z. et al. Drug delivery with carbon nanotubes for in vivo cancer treatment. Cancer Res. 68, 6652–6660 (2008).

    Article  CAS  Google Scholar 

  12. Heller, D.A., Baik, S., Eurell, T.E. & Strano, M.S. Single-walled carbon nanotube spectroscopy in live cells: towards long-term labels and optical sensors. Adv. Mater. 17, 2793–2799 (2005).

    Article  CAS  Google Scholar 

  13. Leeuw, T.K. et al. Single-walled carbon nanotubes in the intact organism: near-IR imaging and biocompatibility studies in Drosophila. Nano Lett. 7, 2650–2654 (2007).

    Article  CAS  Google Scholar 

  14. Chen, Z. et al. Protein microarrays with carbon nanotubes as multicolor Raman labels. Nat. Biotechnol. 26, 1285–1292 (2008).

    Article  CAS  Google Scholar 

  15. Liu, Z. et al. Multiplexed multi-color Raman imaging of live cells with isotopically modified single walled carbon nanotubes. J. Am. Chem. Soc. 130, 13540–13541 (2008).

    Article  CAS  Google Scholar 

  16. Welsher, K., Liu, Z., Daranciang, D. & Dai, H. Selective probing and imaging of cells with single walled carbon nanotubes as near-infrared fluorescent molecules. Nano Lett. 8, 586–590 (2008).

    Article  CAS  Google Scholar 

  17. de la Zerda, L . et al. Photoacoustic molecular imaging in living mice utilizing targeted carbon nanotubes. Nat. Nanotechnol. 3, 557–562 (2008).

    Article  CAS  Google Scholar 

  18. Zavaleta, C. et al. Noninvasive Raman spectroscopy in living mice for evaluation of tumor targeting with carbon nanotubes. Nano Lett. 8, 2800–2805 (2008).

    Article  CAS  Google Scholar 

  19. Qian, X.M. et al. In vivo tumor targeting and spectroscopic detection with surface-enhanced Raman nanoparticle tags. Nat. Biotechnol. 26, 83–90 (2008).

    Article  CAS  Google Scholar 

  20. Alivisatos, A.P., Gu, W.W. & Larabell, C. Quantum dots as cellular probes. Ann. Rev. Biomed. Eng. 7, 55–76 (2005).

    Article  CAS  Google Scholar 

  21. Liu, Z., Sun, X., Nakayama, N. & Dai, H. Supramolecular chemistry on water-soluble carbon nanotubes for drug loading and delivery. ACS Nano 1, 50–56 (2007).

    Article  Google Scholar 

  22. Kam, N.W.S., O'Connell, M., Wisdom, J.A. & Dai, H. Carbon nanotubes as multifunctional biological transporters and near-infrared agents for selective cancer cell destruction. Proc. Natl. Acad. Sci. USA 102, 11600–11605 (2005).

    Article  CAS  Google Scholar 

  23. Chakravarty, P. et al. Thermal ablation of tumor cells with anti body-functionalized single-walled carbon nanotubes. Proc. Natl. Acad. Sci. USA 105, 8697–8702 (2008).

    Article  CAS  Google Scholar 

  24. Zhang, Z.H. et al. Delivery of telomerase reverse transcriptase small interfering RNA in complex with positively charged single-walled carbon nanotubes suppresses tumor growth. Clin. Cancer Res. 12, 4933–4939 (2006).

    Article  CAS  Google Scholar 

  25. Liu, Z. et al. In vivo biodistribution and highly efficient tumour targeting of carbon nanotubes in mice. Nat. Nanotechnol. 2, 47–52 (2007).

    Article  CAS  Google Scholar 

  26. Niyogi, S. et al. Chemistry of single-walled carbon nanotubes. Acc. Chem. Res. 35, 1105–1113 (2002).

    Article  CAS  Google Scholar 

  27. Rosca, I.D., Watari, F., Uo, M. & Akaska, T. Oxidation of multiwalled carbon nanotubes by nitric acid. Carbon 43, 3124–3131 (2005).

    Article  CAS  Google Scholar 

  28. Tagmatarchis, N. & Prato, M. Functionalization of carbon nanotubes via 1,3-dipolar cycloadditions. J. Mater. Chem. 14, 437–439 (2004).

    Article  CAS  Google Scholar 

  29. Liu, Y. et al. Polyethylenimine-grafted multiwalled carbon nanotubes for secure noncovalent immobilization and efficient delivery of DNA. Angew. Chem. Int. Ed. Engl. 44, 4782–4785 (2005).

    Article  CAS  Google Scholar 

  30. Ross, J.S. & Fletcher, J.A. The HER-2/neu oncogene in breast cancer: prognostic factor, predictive factor, and target for therapy. Stem Cells 16, 413–428 (1998).

    Article  CAS  Google Scholar 

  31. Jin, H. & Varner, J. Integrins: roles in cancer development and as treatment targets. Br. J. Cancer 90, 561–565 (2004).

    Article  CAS  Google Scholar 

  32. Cai, W.B. & Chen, X.Y. Preparation of peptide-conjugated quantum dots for tumor vasculature-targeted imaging. Nat. Protoc. 3, 89–96 (2008).

    Article  CAS  Google Scholar 

  33. Anderson, J., Banerjea, A., Planelles, V. & Akkina, R. Potent suppression of HIV type 1 infection by a short hairpin anti-CXCR4 siRNA. AIDS Res. Hum. Retroviruses 19, 699–706 (2003).

    Article  CAS  Google Scholar 

  34. Novina, C.D. et al. siRNA-directed inhibition of HIV-1 infection. Nat. Med. 8, 681–686 (2002).

    Article  CAS  Google Scholar 

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Acknowledgements

The multiple projects involved here were supported by a Stanford Graduate Fellowship, a Stanford Bio-X grant, CCNE-TR at Stanford University, NIH-NCI R01 CA135109-02 and Ensysce Biosciences Inc. Drs Nadine Wong Shi Kam, Sarunya Bangsaruntip, Xiaowu Tang, Xiaoming Sun, Xiaoyuan Chen, Weibo Cai and Ms Nozomi Nakayama have also contributed in the development of this protocol.

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Z.L. and H.D. designed and wrote this paper. S.M.T. and Z.C. revised the paper.

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Correspondence to Zhuo Chen or Hongjie Dai.

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Liu, Z., Tabakman, S., Chen, Z. et al. Preparation of carbon nanotube bioconjugates for biomedical applications. Nat Protoc 4, 1372–1381 (2009). https://doi.org/10.1038/nprot.2009.146

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